The present invention relates to a connection assisting member, particularly to a connection assisting member for connecting a first circuit board having one or more through-holes each of which has a first contact portion formed on an inner surface thereof and a second circuit board having one or more bendable second contact portions.
The present invention also relates to a circuit board assembly in which the first circuit board and the second circuit board are connected by means of the connection assisting member.
A connector for connecting a flexible flat cable to a circuit board such as a flexible printed circuit (FPC) is disclosed by, for example, JP 2005-122901 A. As shown in FIG. 27, this connector is for connecting a plurality of circuit conductors 2 arranged at an FPC 1 and a plurality of flat conductors 4 in a flat cable 3 and is composed of a connector body 5 and a plate member 6 that face each other so as to sandwich an overlap part where the FPC 1 and the flat cable 3 overlap. As shown in FIG. 28, the connector body 5 has a plurality of metallic penetrating pieces 7, while the plate member 6 has a plurality of receiving grooves 8 formed therein.
With the connector body 5 and the plate member 6 being positioned with respect to the FPC 1 and the flat cable 3 such that the penetrating pieces 7 and the receiving grooves 8 separately correspond to the circuit conductors 2 of the FPC 1 and the flat conductors 4 of the flat cable 3, the penetrating pieces 7 of the connector body 5 are thrust into the overlap part where the FPC 1 and the flat cable 3 overlap, and accordingly, the circuit conductors 2 of the FPC 1 and the flat conductors 4 in the flat cable 3 are sheared by the penetrating pieces 7. Upon insertion of the penetrating pieces 7, sheared parts of the circuit conductors 2 and sheared parts of the flat conductors 4 come into contact with the metallic penetrating pieces 7. As a result, the circuit conductors 2 of the FPC 1 and the flat conductors 4 of the flat cable 3 are electrically connected via the penetrating pieces 7.
Meanwhile, the circuit conductors 2 are disposed on a base, made of an insulating material, of the FPC 1, and the flat conductors 4 are covered with an insulating material of the flat cable 3. Therefore, when the penetrating pieces 7 are thrust into the overlap part where the FPC 1 and the flat cable 3 overlap, the base of the FPC 1 is also sheared along with the circuit conductors 2, and the insulating material of the flat cable 3 is also sheared along with the flat conductors 4. Consequently, a sheared piece of the insulating material may be caught between a penetrating piece 7 and a circuit conductor 2 and between a penetrating piece 7 and a flat conductor 4, resulting in a poor contact between the piercing piece 7 and the circuit conductor 2 and between the piercing piece 7 and the flat conductor 4. When such a poor contact occurs, the reliability of electrical connection between the circuit conductors 2 of the FPC 1 and the flat conductors 4 of the flat cable 3 decreases.
In addition, a great force is necessary to thrust the penetrating pieces 7 of the connector body 5 into the FPC 1 at which the circuit conductors 2 are disposed and the flat cable 3 having the flat conductors 4 therein. Accordingly, it is difficult to readily attach the connector body 5 and the plate member 6 to the FPC 1 and the flat cable 3.